Circuit breaker



AVAILABLE CORY;

March 30 1926.

W. M. AUSTEN CIRCUIT BREAKER Filed Sept 16;

1922 I5 Sheets-Sheet l 7 7 ATITORNEY March 30 1926.

W. M. AUSTIN CIRCUIT BREAKER Filed Sept. 16, 1922 3 Sheets-Sheet 2 WITNESSES: F, V INVENTOR 47$ M waver r1. Ausfin.

March 30 1926.

W. M. AUSTIN CIRCUIT BREAKER Filed Sept. l6 1922 3 Sheets-Sheet 3 Fig. 14.

lNVENTOR Walter M. Auslin. ,621

ATTORNEY Patented Mar. 30, 1926.

UNITED STATES PATENT OFFICE.

WALTER M. AUSTIN, SWISSVALE, PENNSYLVANIA, ASSIGNOR TO WESTINGHOUSE I ELECTRIC & MANUFACTURING COMPANY, A CORPORATION OF PENNSYLVANIA.

CIRCUIT BREAKER.

Application filed September 16, 1922. .Serial No. 588,529.

To all when it may concern:

Be it known that I, l/VALTER M. AUsTIN, a citizen of the United States, and a resident of Swissvale, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Circuit Breakers, of which the following is a specification.

My invention relates to circuit breakers and particularly to apparatus for automatically operating circuit breakers.

In some types of circuit breakers, provision is made for effecting the tripping thereof upon the occurrence of predetermined current conditions and, in some cases, it is desirable, also, to prevent the operation of the latching mechanism when such changes in current conditions are of merely momentary duration.

In some cases, a solenoid coil having a movable core is provided, provision being made, in some instances, to adjust the relative positions of the core and the coil, so that the core will be operated under a desired definite current condition-to trip the breaker. Breakers have also been provided with suction devices that delay movement of the core for a desired period of time, during which period the abnormal current condition may have ceased to exist, thus rendering a tripping action unnecessary.

One object of my invention is to provide a simple and compact form of controlling device for circuit breakers that embodies both of the features above referred to, and to simplify and improve generally the construction of the automatic tripping mechanisms of circuit breakers.

As shown in the accompanying drawings,

Figure 1 is a view, in side elevation, of a circuit breaker to which my invention is ap plied,

Fig. 2 is a view, in front elevation, of a portion of the apparatus of Fig. 1,

Figs. 3 and 4 are side elevational and plan views, respectively, of a supporting bracket or pot head which I employ,

Figs. 5 and 6 are plan and side elevational views, respectively, of the movable core member,

.Fig. 7 is a bottom plan view of the suction plate that is carried by a movable core mem ber.

Figs. 8 and 9 are elevational and plan views, respectively, of the scale ring which I employ,

Figs. 10, 11 and 12 are plan and eleva tional views,-respectively, of an adjustable overload element, and 7 Figs. 13, 14 and 15 are plan and eleva tional views, respectively, of the dash-pot.

Referring to Fig. 1, the apparatus is mounted upon a panel 16 to which are secured stationary contact members 17 and arcing tips 18 and 19.

A brush-supporting bracket 21 is pivotally supported at 22 from the panel 16 and carries a brush or bridging member 23 and movable arcing tips 24' and 25. The bridgiug member 23 maybe moved to closed position by means of a handle lever 26 that is pivoted in a bracket 27 and is provided with a cam roller 28. The handle 26 is provided with projecting arms 29 between which a roller or pin 31 may be mounted in position to be engaged by a. latch 32 that is pivoted, at 33, to the frame 27, the latch being normally biased downwardly by a spring 34.

p The breaker is shown as being latched in closed position. Upon upward movement of a tripping lever 35 about its pivotal point 36, the latch 32 will be moved upwardly to disengage the roller 31, by reason of the engagementv of the shoulder. portions 37 and 38 of the lever 35 and latch32, respectively. The latch 32 is provided with a roller 39 to reduce the friction between said latch and the roller or pin .31. The spring 34 also serves to bias the lever 35.. to itsretracted positlon.

The tripping lever 35 may be operated either manually, by its handle portion 41, or by the stem of a movable core member 42 that is moved upwardly under the action of a coil 43 which maybe energized to the desired degree,,under predetermined current conditions in the circuit, as is common in devices of this character. A spring 44 is provided to move the bridging member 23 and the arcing tips 24 and 25 to open position whenever the circuit breaker is tripped.

Upon the underside of the bracket 27, I secure a bracket or pot-head 46, by means of screws 47. The bracket 46 is provided with an arm 48 that is slotted-throughout substantially its entire lengtln-as indicated more clearly in Figs. 1 and 3. An overload-' calibration device 51 (Figs. 10, Hand 12) is provided with threads 52 that co-operate with threads 53 (Figs. 3 and 4) that are formed upon the bracket 46, so that the member 51 may have screw-threaded adjustment relative to the bracket 46 and may be moved rotatively and vertically with respect thereto to bring it to the position shown in Fig. 1. l

The overload device 51 is provided with shoulders 54, as shown more clearly in Fig. 12. A scale ring 55 (Figs. 8 and 9) may be brought into position against the shoulders 54, as shown in Fig. 1. A lug 56 is provided upon the scale ring 55. This lug extends into the slot provided in the arm 48 of the bracket 46 so that the scale ring will be held against rotation.

A. dash-pot or time-element device 57 (Figs. 13, 14 and 15) is provided with ribs 58 and 59, as shown more clearly in Figs. 13 and 15. These ribs are made of a length slightly less than the spaces 61 and 62 between the ends' of ribs 63 and 64, respectively, that are formed upon the overload device 51 (Figs. 11 and 12).

In assembling the apparatus, 46, overload element are assembled as above described. The movable core 42 may then be inserted, such core being provided with a groove 65 (Fig. 5) that engages a rib 66 which is formed upon the bracket 46, so that the core 42 will be held against rotativemovement. When the core has been inserted, the dash-pot 57 may be brought into position by bringing its rib 58 into alinement with the cutaway portion 61 of the rib 63 that is carried upon the the bracket overload element 51 and then rotated until such rib 58 is in alinement with the cutaway portion 62 above described. In this posi tion, the rib 59 will be in alinement with the cutout'portion 61, and the dash-pot 57 may then be raised until the ribs 59 and 58 are above the. ribs 63 and 64, respectively, after which the dash-pot 57 may be rotated until its portion 63, that is provided with a set screw 69, has been brought to the position in Fig. 1. The overload element 51 is similarly provided with a set-screw 71. The dash-pot 57 is provided with shoulders 72 that engage the lower edge of the scale ring 55.

The'interior bottom surface of the dashpot 57 is provided with segmental raised portions 73 that co-operate with segmental raised portions secured to the bottom of the'core 42.

Oil or other viscous fluid is placed in the dash-pot 57, so that, when the raised portions 74 of the piston 75 are brought into partial alinement with the raised portion 73 of the dash-pot, the upward movement of the core 42 will be delayed for a.period of time dependent upon the area of the suction surfaces that are in alinement. p

Rotative movement of the overload element 51 will, by reason of its screw-threaded support upon the bracket 46, cause a raising 51 and scale ring 55 74 of a piston 75, that is or lowering of the dash-pot 57 and, consequently, of the core 42, thus varying the distance between the movable core 42 and stationary core 76 and determining the degree of overload that is required to effect an upward movement of the movable core 42 to trip the latch 32.

The dash-pot 57, may, by its set-screw 69, be clamped to the ring 55 so that, when the overload element 51 is being adjusted, the relative positions of the suction surfaces 7 3 and 74 will not be changed, this owing to the fact that the core 42 is non-rotatable, as above explained, and to the fact that the scale ring 55, by its lug 56, prevents rotation of the ring and the dash-pot 57.

The stepped and circumferentially spaced arrangement of the rings 58 and 59, and the arrangement of the ribs 63 and 64 with their cut-away portions 61 and 62, oppositely disposed, permits of a relative rotative movement of nearly 360 between the dash-pot 57 and the overload member 51, without danger of dislodging the dash-pot. A movement of approximately 90 is sufficient to effect a full range of adjustment of the daslrpot 57, leaving nearly 270 through which the member 51 may be moved, although the pitch of the threads 52 is such that a full range of overload adjustment may be had Within 135.

The ring 55 is provided with a scale along which a pointer moves when the member 51 is being adjusted to the desired degree of overload, to indicate the overload position occupied by the movable core. 7

The pot 57 is likewise provided with a 90 scale that moves along a pointer mark 77 on the ring 55, to indicate the relative rotative positions occupied by the dash-pot and the piston and, consequently, the length of time that is required at a given setting for the magnetism of the coil 43 to overcome the suction between the piston 75 and the raised portions of the dash-pot.

Various modifications and changes may be made without departing from the spirit and scope of the invention, as set forth in the appended claims.

I claim as my invention:

1. The combination with a tripping mechanism for a circuit breaker, of a'magnetically-actuated core member for operating the said mechanism, a segmental suction surface on the under-side of the core memher, a dash-pot for supporting the core iember and provided with a segmental suction surface for ce-cperation withthe first named surface, a supporting bracket, an overload calibration member having screwthreaded connection with the said bracket and serving as a support for the dash-pot, a ring supported by the dash-pot and having non-rotatable connection with the bracket, and clamping means carried by the dash-pot and the said calibration member respectively, whereby either of the last named members may engage the said ring to be thereby held against rotative movement.

2. The combination with a solenoid coil provided with a movable core, 01 means for retarding the movement-0f the core comprising a load calibration member having screw-threaded adjustment and a time-element device rotatably supported by the said member, a collar supported by the time-element device, means for holding the collar against rotative movement and clamping means cooperating with the collar to hold either the calibration member or the timeelement device against rotative movement while the other is being adjusted.

3. The combination with a solenoid coil provided with a movable core, of means for retarding the movement of the core comprising a load calibration member havin rotatable adjustment and a time-element device rotatably supported by said member, a collar co-operatively related to said member and device, means for holding the collar against rotative movement and clamping means co-operating with the collar to hold either the calibrating member or the timeelement device against rotative movement while the other is being adjusted.

4. The combination with a tripping mechanism for a circuit breaker, of a magnetically-actuated core member for operating the said mechanism, retarding means secured to the core member, a dash-pot for supporting the core member and provided with retarding means for co-operation with the first named retarding means, a support ing bracket, an overload calibration memher having screw-threaded connection with the said bracket and serving as a support for the dash-pot, a ring supported by the dash-pot and having non-rotatable connection with the bracket, and clamping means carried by the dash-pot and the said calibration member respectively, whereby either of the last-named members may engage the said ring to be thereby held against rotative movement.

I11 testimony whereof, I have hereunto subscribed my name this 25th day of August, 1922.

'WALTER M. AUSTIN. 

